Every four years a leap day helped keep things on track.

四年一闰，闰年于二月底增加一闰日以保证万物步入正轨。

Determines whether the specified day is a leap day.

确定指定的日期是否为闰日。

When overridden in a derived class, determines whether a date is a leap day.

在衍生类别覆写时，判断某个日期是否为闰日。

They know that in a leap year, they have "one more day" to improve their overall results.

他们知道在闰年的时候，他们能够有“多一天”来提高他们的总产量。

There are other tricks to assist with dates in the first months of the year—for example, the last day of February is always an anchor day, leap year or no.

还有一些其他技巧可以帮助你确定一年的头几个月的日期——例如，二月的最后一天总是锚日，不管闰年还是平年。